Ensure zip file directory always exists when doing a release.
Ensure zip file directory always exists when doing a release.

Fixes crash when file not found creating ZipFile.
	Change on 2015/10/22 by johncox <johncox@google.com>
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=106098637

andela-angene/coursebuilder-core,andela-angene/coursebuilder-core,andela-angene/coursebuilder-core,andela-angene/coursebuilder-core